Markers for visualizing interventional medical devices

• US 20050149002A1
• Filed: 11/29/2004
• Published: 07/07/2005
• Est. Priority Date: 04/08/2003
• Status: Abandoned Application

• Current Assignee: Biophan Technologies Incorporated
• Original Assignee: Biophan Technologies Incorporated
• Inventors: Wang, Xingwu, Shellock, Frank G.
• Application Number:
  US10/999,185
• Publication Number:
  US 20050149002A1
• Time in Patent Office: Days
• US Class Current: 606/1
• CPC Class Codes: A61B 2017/00831 Material properties
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2250/0045 differing in electromagnetical properties
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61L 29/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque

Abstract

A marking material that, when disposed upon medical devices used during interventional medical procedures with imaging modalities such as X-ray Fluoroscopy and Magnetic Resonance Imaging, renders such medical devices visible with minimal imaging artifacts. The material comprises a particulate material with generally higher atomic weight disposed within a matrix material with generally lower atomic weight. In one embodiment the particulate material is magnetic. In another embodiment the particulate material is non-magnetic.

Claims

1. A medical device assembly that is insertable into the body of a patient, said medical device assembly comprising:

a surface and a marking material disposed on at least a portion of said surface, wherein said marking material is comprised of a particulate material disposed in a matrix material, wherein said particulate material is comprised of a plurality of first atoms and a plurality of second atoms, wherein said matrix material is comprised of a plurality of said second atoms and a plurality of third atoms, wherein said first atoms have an atomic weight at least twice the atomic weight of said second atoms and twice the atomic weight of said third atoms, and wherein the average particle size of said particulate material is less than 100 nanometers.

2. The medical device assembly recited in claim 1, wherein the atomic weight of said first atoms is in the range from about 30 to about 300.

3. The medical device assembly recited in claim 2, wherein the atomic weight of said first atoms is in the range from about 50 to about 260.

4. The medical device assembly recited in claim 3, wherein said first atoms are chosen from the group consisting of Chromium, Manganese, Iron, Cobalt, Nickel, Copper, Zinc, Gallium, Germanium, Selenium, Strontium, Yttrium, Zirconium, Molybdenum, Neodymium, Samarium, Gadolinium, and combinations thereof.

5. The medical device assembly recited in claim 3, wherein the atomic weight of said second atoms and the atomic weight of said third atoms is less than 30.

6. The medical device assembly recited in claim 5, wherein said second atoms and said third atoms are chosen from the group consisting of Boron, Carbon, Nitrogen, Oxygen, Magnesium, Aluminum, Silicon, and combinations thereof.

7. The medical device assembly recited in claim 5, wherein the atomic weight of said second atoms and the atomic weight of said third atoms is less than 20.

8. The medical device assembly recited in claim 5, wherein the electrical conductivity of said particulate material is at least three times the electrical conductivity of said matrix material.

9. The medical device assembly recited in claim 5, wherein the dielectric constant of said particulate material is less than the dielectric constant of said matrix material.

10. The medical device assembly recited in claim 9, wherein the dielectric constant of said particulate material is about 0.3 to about 0.5 of the dielectric constant of said matrix material.

11. The medical device assembly recited in claim 5, wherein said particulate material is non-magnetic.

12. The medical device assembly recited in claim 11, wherein said particulate material has an electrical surface resistivity of 1000×

10<sup>−

8</sup> Ω

-m or less.

13. The medical device assembly recited in claim 12, wherein said particulate material has an average particle size of less than 60 nanometers.

14. The medical device assembly recited in claim 12, wherein said particulate material has an electrical surface resistivity of 10×

10<sup>−

8</sup> Ω

-m or less.

15. The medical device assembly recited in claim 14, wherein said particulate material has an average particle size of less than 60 nanometers.

16. The medical device assembly recited in claim 5, wherein said particulate material is a magnetic material.

17. The medical device assembly recited in claim 16, wherein said first atoms are chosen from the group consisting of Cr, Mn, Fe, Co, Ni, and combinations thereof.

18. The medical device assembly recited in claim 5, wherein said particulate material is comprised of nanomagnetic particles.

19. The medical device assembly recited in claim 18, wherein said nanomagnetic particles have a direct current permeability at a static magnetic field of 1.5 Tesla of from about 1.1 to about 2.0.

20. The medical device assembly recited in claim 18, wherein the average particle size of said nanomagnetic particles is from about 3 to about 10 nanometers.

21. The medical device assembly recited in claim 18, wherein said nanomagnetic particles have a coherence length of less than 100 nanometers.

22. The medical device assembly as recited in claim 18, wherein said nanomagnetic particles have an average particle size of less than about 20 nanometers and a phase transition temperature of less than about 200 degrees Celsius.

23. The medical device assembly as recited in claim 18, wherein the average particle size of said nanomagnetic particles is less than about 15 nanometers.

24. The medical device assembly as recited in claim 18, wherein said nanomagnetic particles have a squareness of from about 0.05 to about 1.0.

25. The medical device assembly as recited in claim 18, wherein said nanomagnetic particles have a squareness of from about 0.1 to about 0.9.

26. The medical device assembly as recited in claim 18, wherein said nanomagnetic particles have a squareness of from about 0.2 to about 0.8.

27. The medical device assembly as recited in claim 18, wherein said nanomagnetic particles have an average particle size of less than about 3 nanometers.

28. The medical device assembly as recited in claim 18, wherein said nanomagnetic particles have a phase transition temperature of less than about 46 degrees Celsius.

29. The medical device assembly as recited in claim 18, wherein said nanomagnetic particles have a phase transition temperature of less than about 50 degrees Celsius.

30. The medical device assembly as recited in claim 18, wherein said nanomagnetic particles have a coercive force of from about 0.01 to about 5,000 Oersteds.

31. The medical device assembly as recited in claim 18, wherein said first atoms are comprised of iron and said second atoms are comprised of aluminum.

32. The medical device assembly as recited in claim 31, wherein said nanomagnetic particles are comprised of less than 50 weight percent of iron, by total weight of iron and aluminum.

33. The medical device assembly as recited in claim 31, wherein said nanomagnetic particles are comprised of from about 5 to about 40 weight percent of iron, by total weight of iron and aluminum.

34. The medical device assembly as recited in claim 31, wherein said nanomagnetic particles are comprised of from about 5 to about 30 weight percent of iron, by total weight of iron and aluminum.

35. The medical device assembly as recited in claim 31, wherein said nanomagnetic particles are comprised of from about 5 to about 20 weight percent of iron, by total weight of Iron and aluminum.

36. The medical device assembly as recited in claim 5, wherein said medical device is a catheter.

37. The medical device assembly as recited in claim 5, wherein said medical device is a stent.

38. A medical device assembly that is insertable into the body of a patient, said medical device assembly comprising:

a surface and a marking material disposed in the form of a film on at least a portion of said surface, wherein said film has a thickness of from about 400 to about 2000 nanometers, wherein said marking material is comprised of a particulate material disposed in a matrix material, wherein said particulate material is comprised of a plurality of first atoms and a plurality of second atoms, wherein said matrix material is comprised of a plurality of said second atoms and a plurality of third atoms, wherein said first atoms have an atomic weight at least twice the atomic weight of said second atoms and twice the atomic weight of said third atoms, and wherein the average particle size of said particulate material is less than 100 nanometers.

39. The medical device assembly as recited in claim 38, wherein said film has a thickness of from about 600 to about 1200 nanometers.

40. The medical device assembly recited in claim 38, wherein the atomic weight of said first atoms is in the range from about 30 to about 300.

41. The medical device assembly recited in claim 40, wherein the atomic weight of said first atoms is in the range from about 50 to about 260.

42. The medical device assembly recited in claim 41, wherein said first atoms are chosen from the group consisting of Chromium, Manganese, Iron, Cobalt, Nickel, Copper, Zinc, Gallium, Germanium, Selenium, Strontium, Yttrium, Zirconium, Molybdenum, Neodyium, Samarium, Gadolinium, and combinations thereof.

43. The medical device assembly recited in claim 41, wherein the atomic weight of said second atoms and the atomic weight of said third atoms is less than 30.

44. The medical device assembly recited in claim 43, wherein said second atoms and said third atoms are chosen from the group consisting of Boron, Carbon, Nitrogen, Oxygen, Magnesium, Aluminum, Silicon, and combinations thereof.

45. The medical device assembly recited in claim 43, wherein the atomic weight of said second atoms and the atomic weight of said third atoms is less than 20.

46. The medical device assembly recited in claim 43, wherein the electrical conductivity of said particulate material is at least three times the electrical conductivity of said matrix material.

47. The medical device assembly recited in claim 43, wherein the dielectric constant of said particulate material is less than the dielectric constant of said matrix material.

48. The medical device assembly recited in claim 47, wherein the dielectric constant of said particulate material is about 0.3 to about 0.5 of the dielectric constant of said matrix material.

49. The medical device assembly recited in claim 43, wherein said particulate material is non-magnetic.

50. The medical device assembly recited in claim 49, wherein said particulate material has an electrical surface resistivity of 1000×

10<sup>−

8</sup> Ω

-m or less.

51. The medical device assembly recited in claim 50, wherein said particulate material has an average particle size of less than 60 nanometers.

52. The medical device assembly recited in claim 50, wherein said particulate material has an electrical surface resistivity of 10×

10<sup>−

8</sup> Ω

-m or less.

53. The medical device assembly recited in claim 52, wherein said particulate material has an average particle size of less than 60 nanometers.

54. The medical device assembly recited in claim 43, wherein said particulate material is a magnetic material.

55. The medical device assembly recited in claim 54, wherein said first atoms are chosen from the group consisting of Cr, Mn, Fe, Co, Ni, and combinations thereof.

56. The medical device assembly recited in claim 43, wherein said particulate material is comprised of nanomagnetic particles.

57. The medical device assembly recited in claim 56, wherein said nanomagnetic particles have a direct current permeability at a static magnetic field of 1.5 Tesla of from about 1.1 to about 2.0.

58. The medical device assembly recited in claim 56, wherein the average particle size of said nanomagnetic particles is from about 3 to about 10 nanometers.

59. The medical device assembly recited in claim 56, wherein said nanomagnetic particles have a coherence length of less than 100 nanometers.

60. The medical device assembly as recited in claim 56, wherein said nanomagnetic particles have an average particle size of less than about 20 nanometers and a phase transition temperature of less than about 200 degrees Celsius.

61. The medical device assembly as recited in claim 56, wherein the average particle size of said nanomagnetic particles is less than about 15 nanometers.

62. The medical device assembly as recited in claim 56, wherein said nanomagnetic particles have a squareness of from about 0.05 to about 1.0.

63. The medical device assembly as recited in claim 56, wherein said nanomagnetic particles have a squareness of from about 0.1 to about 0.9.

64. The medical device assembly as recited in claim 56, wherein said nanomagnetic particles have a squareness of from about 0.2 to about 0.8.

65. The medical device assembly as recited in claim 56, wherein said nanomagnetic particles have an average particle size of less than about 3 nanometers.

66. The medical device assembly as recited in claim 56, wherein said nanomagnetic particles have a phase transition temperature of less than about 46 degrees Celsius.

67. The medical device assembly as recited in claim 56, wherein said nanomagnetic particles have a phase transition temperature of less than about 60 degrees Celsius.

68. The medical device assembly as recited in claim 56, wherein said nanomagnetic particles have a coercive force of from about 0.01 to about 5,000 Oersteds.

69. The medical device assembly as recited in claim 56, wherein said first atoms are comprised of iron and said second atoms are comprised of aluminum.

70. The medical device assembly as recited in claim 69, wherein said nanomagnetic particles are comprised of less than 50 weight percent of iron, by total weight of iron and aluminum.

71. The medical device assembly as recited in claim 69, wherein said nanomagnetic particles are comprised of from about 5 to about 40 weight percent of iron, by total weight of iron and aluminum.

72. The medical device assembly as recited in claim 69, wherein said nanomagnetic particles are comprised of from about 5 to about 30 weight percent of iron, by total weight of iron and aluminum.

73. The medical device assembly as recited in claim 69, wherein said nanomagnetic particles are comprised of from about 5 to about 20 weight percent of iron, by total weight of iron and aluminum.

74. The medical device assembly as recited in claim 43, wherein said medical device is a catheter.

75. The medical device assembly as recited in claim 43, wherein said medical device is a stent.